Sphygmograph.



No. 747,157. PATENTED DEC. 15, 1903. W. H. PAHRNEY.

SPHYGMOGRAPH.

APPLIOATIOH FILED APR. 24, 1903.

H0 KODEL. 4 SHEETS-SHEET 1.

rm: uonws warms co. PHOTOLITNOH WASHINGTON, n, c

No. 747,157. PATENTBD DEO.15, 1903.

W. H.. FAHRNEY. SPHYGMOGRAPH.

APPLICATION TILED APR. 24, 1903.

4 SHEETS-SHEET 2.

I0 IODEL.

PATENTED DEC. 15, 1903.

- .w. H. PAHRNBY. SPHYGMOGRAPH.

APIQLIOATIOK FILED APR. 24, 1903.

4 SHEETS-SHEET 3.

' N0 MODEL.

"In"! IIIIIIIIIR X uvlmm :umnu:

Wvwsesa No. 747,157. PATENTED DEG.-15, 1903. W. H. FAHRNEY. SPHY GMOGRAPH.

APPLIOATION FILED APR. 24, 1903.

NO XODEL.

4 SHEETS-SHEET 4.

' UNITED "ST TES Patented December 15, 1903.

WILLIAM H. FAHRNEY, OF CHICAGO, ILLINOIS.

S PHYGMOGRAPH.

SPECIFICATION formingpart of Letters Patent No. 747,157, dated December 15, 1903.

Application filed April 24, 1903. Serial No; 154,144. \No model.)

To all whomit may concern:

Be it known that I, WILLIAM H. FAHRNEY, a citizen of the United States,residing at Ohicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Sphygmographs, of which the following is a full, clear, and exact specification.

My invention relates to sphygmographs for indicating or recording the hearts pulsation or anyother like action; and the invention has for its primary object to provide a simple and improved form of device for such purpose or purposes especially adapted for indicating such pulsation or action by variations or undulations in an electric current.

Another object of my invention is to provide improved and efficient means for producing a permanent record of such pulsation or action; and a further object of my invention is to produce means whereby the position at which the gage of the wrist-piece of the sphygmograph has to be set for each patient may be determined, so that when the same patient calls again the gage may be readily readjusted to the position required by that particular patient. 7

With these ends in view my invention consists in certain features of novelty in the construction, combination, and arrangement of parts by which the said objects and certain other objects hereinafter appearing are attained, all as fully described with reference to the accompanying drawings and more particularly pointed out in the claims.

In the said drawings, Figure 1 is a perspective view of my improved apparatus. Fig. 2 is a cross-section thereof, taken on the line 2 2, Fig. 1. Fig. 3 is a detail vertical section taken on the line 3 3, Fig. 2. Fig. 4 is a detail perspective view of the magnet and connected parts for controlling the motor mechanism. Fig. 5 is a detail plan view of the receptacle for the chemical bath, showing the paper strip and the rollers. Fig. 6 is a diagrammatic view of the apparatus and electric circuits. Fig. 7 is a detail vertical section of the wrist-piece of the sphygmograph; and Fig. 8 is a diagrammatic view similar to Fig. 6, illustrating the modification hereinafter explained.

In this invention the pulsations produce variations in the strength of an electric circuit,

and these variations set up induced currents in an induction-coil whose secondary wire is connected with the coil of an electromagnetic device which is suitably connected with an electric needle arranged to move back and forth in obedience to the variations in the current across a strip of paper which passes through a suitable chemical bath, such as iodid of potassium, and completes the circuit between said needle and a roller or other surface on which the paper rests, and which roller is electrically connected with one pole of a battery, while the needle is similarly connected with the other pole through the intermediary of a switch under the control of the operator, and which switch when closed sets in operation a motor for feeding the paper at a uniform speed under the electric needle, whereby the iodid of potassium is decomposed wherever the needle touches during the travel of the paper or other recording surface. As a means of producing these variations in the current by the pulsations I employ any suitable variable resistance or conductor and preferably that which is shown in the drawings and which consitutes the subject-matter of the claims of my pending application, Serial No. 138,464, filed January 10, 1903, and which may be briefly described as consisting of a shell 1, in the upper end of which is secured a bushing 2, of any suitable insulating material, forming a means of carrying a rod 3, Whose outer end is provided with a binding-post B, while its inner end is attached to an elastic tube 5, filled with granulated carbon or other suitable material 6 and having its lower end attached to a rod 7, upon which is secured a nut 8, supporting the lower end of a spring 9, which surrounds the bushing 2 and bears against the upper end of shell 1. The lower end of rod 7 is provided with a button 10 of any suitable shape for contact with the pulse of the patient. This button 10 protrudes at central aperture 11 in an adjustable gage 12, screwed on the lower end of shell 1 in such a way that the protrusion of button 10 relatively to gage 12 may be varied to suit the peculiarities of different patients, it being understood that the pulse of one may be deeper than that of another, and therefore requires greater projection of the apparatus with the other pole of the electric button 10, while the gage 12 rests firmly against the wrist.

In my present invention the gage 12 is provided with a sleeve 13, which is screwthreaded on the exterior of shell 1 and has its upper edge or end provided with a series of graduations, as more clearly shown in Fig. 1, numbered consecutively from 1 up, the number of graduations employed being governed simply by the size of diameter of the sleeve 13. In order that the graduations may be more readily observed, the end of the sleeve is beveled, as shown in Figs. 1 and 7. On the side of the shell 1 adjacent to the end of the sleeve 13 is a vertical index or graduation 14, with which all of the graduations on 13 are adapted to register as the latter is rotated, and this vertical index let is divided perpendicularly by cross-graduations,which may be designated A, B, C, D, orgiven any other suitable designation to distinguish them from the numbered graduations on 13. With the device thus provided with graduations it will be seen that, assuming the upper end of the sleeve 13 to be at or slightly above the transverse graduations A when the gage 12 is screwed upward as far as it will go, it is simply necessary in order to obtain a record of the position or adjustment of the gage for any particular patient to note the number of the graduation on 13, which registers with index 14 when the sleeve has been screwed downwardly to the place where the pulse recorc s best, and to also note the transverse graduation A, B, C, or D, which is immediately above the upper end of the sleeve 13. Hence even though it may be necessary to turn the sleeve 13 a number of times before the desired adjustment is reached the letter of the transverse graduations, read in connection with the numbers of the graduations on 13, will give the exact position for any particular patient, and by recording the letter and the number the device may be readily adjusted when the patient calls again. The graduations A, B, C, D are supposed to be as far apart as the screw-threads which connect the sleeve to the shell, and hence the end of the sleeve would pass one of the graduations A, E, G, D each time the sleeve is given a complete rotation.

The granulated material 6 is electrically connected to the shell 1 through the rod 7, the nut 8, and spring 9, and in order that the shell may be conveniently connected with a source of electricity it is provided with a binding-post O on one end, rod 3 having a binding-post B for convenience in connecting the source.

In order that the wrist-piece thus described may be moved about conveniently for application to the wrist of the patient independently of the recording mechanism, it is connected with the latter by elongated flexible conductors, preferably running to suitable binding-posts. The binding-post C is therefore connected by conductor 15 with a binding-post O, secured on the box or casing 16 of the recording apparatus, and binding-post B by conductor 17 with binding-post B. The binding-post B is connected by conductor 18 with one pole of battery 19, and binding-post C is connected by conductor 20 with one pole of the primary coil of an induction-coil 21, whose other pole is connected by conductor 22 with the other pole of battery 19. The secondary coil of the induction-coil 21 is connected by conductors 23 2Awith the terminals of a solenoid 25 or other suitable electromagnetic device having a core or armature 26 controlled thereby, so that when the primary circuit, passing through the primary coil of induction-coil 21, is varied in strength by variations in pressure on the button 10 the current will pass from battery 19 along conductor 22 through the primary induction-coil, conductors 20 and 15, red 7, resistance 6, rod 3, conductor 17, and conductor 13 back to the battery, thus inducing a current in the secondary in d notion-coil, and thereby energizing the solenoid 25, which causes its core or armature 26 to move back and forth in harmony with the variation in pressure against the button 10. The armature 26 is suitably connected with an electric needle 27, which rests upon a metallic roller 23 or roller composed of any other suitable conductor of electricity, and between this roller and needle passes a strip of paper or other suitable recording-sun face 29 which has been previously saturated with any suitable chemical capable of being decomposed and producing discoloration by the passage of an electric current therethrough. The needle 27 is electrically connected to one pole of the battery 19 by aconductor 30, and the roller 28 is electricallyconnected to a movable contact 31, supported on. an armature 32. In the apparatus this connection between the roller28 and the contact or switch 31 is effected through a plate 33, in which the roller is journaled, and a plate 34 in contact with plate 33 and also in contact with a supporting member 35 of the armature 32; but in the diagrammatic view these plates and other electrical connections between the armature 32 and roller 28 may be represent.- ed by the line or conductor 36. The switch or contact 31 is adapted to connect with a fixed contact 37, which is connected by conductor 38 with battery 19. The armature 32 is under the control of an electromagnet 39, having one pole connected with battery 19 by conductor 40 and the other pole to a switch or push-button 41, mounted for convenience upon the end of shell 1 and adapted to be depressed in electrical engagement with binding-post B or any other suitable contact in electrical connection with conductor 17 and battery 19 through conductor 18. This connection between switch i1 and the other pole of magnet 39 is effected through a conductor a2, which leads to a binding-post A, and a ICC conductor 43, leading from binding-post A to switch 41. For convenience a third binding-post A is provided on shell 1 for the attachment of conductor 43, which is carried through to the switch 41. When switch 41 is closed, the magnet 39 will be energized through 22, 40, 42, 43, A, 41, 17, and 18, thereby attracting armature 32 and closing the circuit through 22, 30, 27, 28, 36, 32, 31, 37, 33, 18, and 19, thus passing the battery-current through the paper strip 29, where it rests upon the roller 28, and decomposing the chemical thereon to produce a mark wherever the point 27 draws, as before described. This action of the armature 32 also sets in action a suitable motor or clock mechanism for propelling the strip 29 across the roller 28 by means substantially as follows: As shown in Figs. 2, 4, and 6, the armature 32 is provided with a stop 44, which while the magnet 39 is deenergized remains in engagement with one end of a fan or other suitable governor 45, whichis geared to a train of gearing 46 of a suitable motor or clock mechanism, serving by suitable gear connection with a feed-roller 47 to'rotate said roller 47 when the fan or governor 45 is released, and by thus rotating against the strip 29 while the latter is pressed against roller 47 by a pressure-roller 48 the strip is drawn across the roller 28 under the needle-point, and it is of course understood that the strip will thus continueto move as long as the finger of the operator holds the switch 41 depressed.

In the diagrammatic illustrations of the invention the needle 27 by reason of the relation in which it is shown to the core 26 would vibrate lengthwise of the strip 29 in obedience to the variations in pressure upon button 10; but this relation of the needle to the strip in these diagrams is shown merely for convenience of illustration, and in practice the needle 27 must move transversely of the line of movement of the strip 29 by means of some such mechanism as that illustrated in Figs. 1, 2, 3, and 5 of the drawings and which will now be described. Mounted upon the plate 33 is a block 49, of suitable insulation, provided with a central aperture 50, and below the plate 33, just under this aperture 50, is arranged the solenoid 25,whose core 26 passes downwardly through the aperture 50 and plate 33 and has its upper end screwthreadcd, as shown at 51, and thereby secured in a stem 52, so that the core 26 may be adjusted with relation to a chain or other flexible connection 53, which has one end attached to stem 52 and the other end passing over and attached to a drum or pulley 54, being a jam-nut whereby the adjustment of 51 and 52 may be maintained. Pulley 54 is fixed to a shaft 56, journaled in suitable bearings 57, mounted in a frame 58, which is supported by an arm 59 on a standard 60, mounted on the block ofinsulation 49, the standard 60, arm 59, frame 58, bearings 57, and shaft 56 being electrical conductors for conveying the current.

to the needle 27, which is attached to the lower end of a swinging arm secured to the shaft 56 and preferably composed of a U- shaped wire or rod 61, the needle 27 being soldered or otherwise secured to the lower end thereof and com posed of platinum or any other suitable material. The core 26 is supported by a spiral spring 62, resting upon the plate 33 in the aperture 50 and bearing under a nut 63 on the threaded portion 51, so that when solenoid 25 is denergized the core will be elevated or returned to its normal position, and the shaft 56 may be rotated backwardly to return the needle 27 to its normal position and rewind chain 53 on pulley 54 by means of any suitable spring 64, coiled around and secured to shaft 56 at one end and at its other end to the frame 58 by means of set-screw 65, which passes through the frame and pinches spring 64 against a loop 66, secured to the under side of frame 58. 67 is a stop for limiting the outward throw of arm 61, and 63 is a similar stop for limiting its return movement. The electrical communication between standard and one pole of the battery is established through conductor 30, which may be in the form of an insulated wire secured to the lower end of standard 60 and passing downwardly through plate 33 to the battery 19, which may be located in a compartment 69. in the diagrammatic view this conductor 30 is shown as extending directly to the needle 27.

70 is a receptacle for containing a small quantity of any suitable chemical, such as iodideot' potassium,(indicated at 71,) that will be decomposed by the passage of the electric current through the paper strip 29, which lat-- ter passes downwardly into the receptacle 70, first over a suitableguide-roller 72 and thence under a depressing-roller 73, which holds a part of the strip submerged, and from the latter roller it passes upwardly over the rolleis 28 47. The roller 73 is shown as mounted in a vertically-sliding frame 74, having a cross-bar or handle 75, adapting it to be pushed downwardly into the receptacle 70 between two guide-strips 76, secured on each side of the receptacle 70.

77 is a spring secured to plate 33 and hearing upon a reduced portion 78 of roller48 for holding the latter down against the roller 47 with sufficient pressure to cause the paper to feed, the roller 48 being mounted in slots 79 in the bearing-pieces 30, supported on plate 30.

When the device is not in use, the battery may be saved by opening any suitable switch 81 in the battery-circuit.

In the form of the invention shown in Fig. 8 the induction-coil 21 is omitted and the conductor 20 is carried directly from bindingpost C to one pole of the solenoid 25, while the conductor 24, leading from the other pole of the solenoid, is carried directly to conductor 22, which goes to the battery 19. hen the induction-coil 21 is employed, however, it will be seen that the current would pass through the solenoid 25 only when the primary current is varied by the pulsation of button 10, and consequently, although the needle 27 may jump to the farther side of the paper strip 29 when the button 10 is first pressed against the pulse, the solenoid 25 becomes deenergized the instant after the first impulse has passed through it, and consequently the spring 64 will restore the needle 27 to its central position on the paper strip, where it will remain until the pressure against the button 10 is again varied by the pulse beats, thus producing a record always in the center of the strip 29, as shown in Fig. 5; but with the form shown in Fig. 8, in which the induction-coil is omitted and which is suitable for some purposes, the needle 27 will be thrown to one side of the paper strip 29 as soon as the switch 81 is closed, because at that instant the solenoid 25 becomes permanently energized and holds the needle in its outward position or near the edge of the strip until the strength of the current is varied either by increase or decrease of pressure on the button 10.

Having thus described my invention, what I claim as new therein, and desire to secure by Letters Patent, is

1. In a sphygmograph, the combination of a variable conductor of electricity, an electric circuit including said conductor, means included in said circuit for indicating variations in the current strength thereof, means for causing said variable conductor to vary the strength of said circuit, a movable gage operatively related to said second means, a scale of graduations fixed with relation to said gage, and a scale of graduations movable with said gage and arranged to be read in conjunction with said first scale.

2. In a sphygmograph, the combination of a variable electrical conductor, an electric circuit including said conductor, means in said circuit for indicating variations in the strength thereof, means for operating said variable conductor to vary the strength of said circuit, a gage movable with relation to said operating means, a casing inclosing said operating means and variable conductor and with which said gage has screw-threaded connection, and two scales of graduations on said casing a gage respectively, arranged to be read in connection with each other.

3. In a sphygmograph, the combination of a variable electrical conductor, an electric circuit including said conductor, means operatively related to said circuit for indicating variations in the strength thereof, a second circuit, means controlled by said second circuit for moving a recording-surface past said indicating means, and a switch for opening and closing said second circuit.

a. In a sphygmograph, the combination of a variable electrical conductor, an electric circuit including said conductor, means for operating said conductor to vary the strength of said circuit, means included in said circuit for indicating said variations, said variable resistance and operating means being compressed in a portable wrist-piece movable independently of said indicating means, a second electric circuit, a switch carried by said portable wrist-piece for closing said second circuit, and means controlled by said second circuit for moving a record-surface past the said indicating means.

5. In a sphygmograph, the combination of avariable electrical conductor, an electric circuit including said conductor, means for operating said variable conductor to produce undulations in said circuit, means for recording said undulations operatively related to said circuit, a second electric circuit, means controlled thereby for moving a recordingsurface past said recording means, and means for opening and closing said second circuit at will.

6. In a sphygmograph, the combination of an electric circuit, means for producing undulations therein, means for recording said undulations operatively related to said circuit, a motor mechanism for moving a recording-surface past said recording means, and a second circuit controlling said motor mechanism.

7. In a sphygmograph, the combination of an electric circuit, means for producing undulations therein, means for recording said undulations operatively related to said circuit and comprising a recording-point, a second circuit including said recording-point, and means for closing said second circuit at will.

8. In a sphygmograph, the combination of an electric circuit, means for producing undulations therein, means operatively related to said circuit for recording said undulations comprising a recording-point, means for moving a recording-surface past said recordingpoint, a second circuit including said recording-point, a third circuit controlling the last said means, and means for closing said third circuit at will.

9. In a sphygrnograph, the combination of an electric circuit, means for producing undulations therein, means operatively related to said circuit for recording said undulations, an independently-acting motor mechanism for moving a recording-surface past said recording means, a lock for holding said motor mechanism inactive, a second circuit, means for closing the same at will, and an electric device in said second circuit for controlling said lock.

10. In a sphygmograph, the combination of an electric circuit, means for producing undulations therein, a rocker-shaft, an arm secured to said shaft, a recording-needle attached to said arm, a drum or pulley on said shaft, a solenoid operatively related to said circuit and having a core, a flexible connection between said core and pulley, and means for returning said arm to normal position.

11. In a sphygmograph, the combination of an electric circuit, means for producing undulations therein, a rocker-shaft, an arm secured thereto, a recording-needle attached to said arm, a drum or pulley on said shaft, a solenoid operatively related to said circuit and having a core, a flexible connection secured to said pulley, and an adjustable connection between said core and flexible connection.

12. In a sphygmograph, the combination of an electric circuit, means for producing undulations therein, a solenoid operatively related to said circuit and comprising a core, a spring supporting said core, a rocker-shaft, an arm secured to said shaft, a recording-needle attached to said arm, a pulley on said shaft, a flexible connection between said core and pulley, and a spring attached to said shaft for winding the flexible connection on said pulley.

13. In a sphygmograph, the combination of an electric circuit, means for producing undulations therein, means operatively related to said circuit for actuating a recording-needle, and an electric conducting-surface 0pposed to said needle, means for passing a current through said needle and surface, a recording-strip passing between said needle and surface, a receptacle for a chemical, and means for depressing said strip in said receptacle prior to passing said recording-needle.

14. In a sphygmograph, the combination of an electric circuit, means for prod ucing undulations therein, means operatively related to said circuit for recording said undulations, means for feeding a recording-strip past said recording means, a receptacle for a chemical, and a vertically-slidable frame for depressing said strip into said receptacle.

WILLIAM H. FAHRNEY.

Witnesses:

F. A. HOPKINS, M. B. ALLs'rADT. 

